System and method for automatically learning and maintaining IP address allocation topology

Abstract

A topology map engine obtains, from a dynamic host control protocol relay device, a relayed request, of a client, for a dynamic host control protocol lease. The relayed request has at least one given IP address of the dynamic host control protocol relay device inserted therein. A search is made in a database for that IP address. If not found, dynamic host control protocol relay device information is obtained. This information includes: an identifier of the dynamic host control protocol relay device; and at least one network interface of the dynamic host control protocol relay device and any internet protocol addresses assigned to same. This information is obtained at the topology map engine and stored in the database.

What is claimed is: 
     
       1. A method comprising the steps of:
 obtaining, at a topology map engine, from a dynamic host control protocol relay device, via a lease forwarder on a dynamic host control protocol server downstream of the topology map engine and upstream of the dynamic host control protocol relay device, a relayed request, of a client, for a dynamic host control protocol lease, said relayed request having at least one given internet protocol address of said dynamic host control protocol relay device inserted therein; 
 searching, in a database collocated with said topology map engine, for said at least one given internet protocol address of said dynamic host control protocol relay device; 
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, performing an automated process to discover each of one or more internet protocol subnets configured on said dynamic host control protocol relay device, said process comprising the steps of:
 obtaining, at said topology map engine, from said dynamic host control protocol relay device, dynamic host control protocol relay device information comprising at least:
 an identifier of said dynamic host control protocol relay device, said identifier of said dynamic host protocol relay device being distinct from said at least one given internet protocol address of said dynamic host control protocol relay device inserted in said relayed request; and 
 at least one network interface of said dynamic host control protocol relay device and any internet protocol address assigned to said at least one network interface of said dynamic host control protocol relay device; and 
 
 storing said dynamic host control protocol relay device information in said database. 
 
 
     
     
       2. The method of  claim 1 , wherein in said step of obtaining said dynamic host control protocol relay device information, said identifier comprises a permanent identifier. 
     
     
       3. The method of  claim 2 , further comprising:
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, sending a query, from said topology map engine, back to said dynamic host control protocol relay device, for said dynamic host control protocol relay device information; 
 wherein said dynamic host control protocol relay device information comprises:
 said permanent identifier of said dynamic host control protocol relay device; 
 all network interfaces of said dynamic host control protocol relay device; and 
 all internet protocol addresses, including said at least one given internet protocol address, assigned to said network interfaces of said dynamic host control protocol relay device. 
 
 
     
     
       4. The method of  claim 3 , wherein, in said step of obtaining said relayed request, said relayed request comprises an Internet Protocol Version 6 (IPv6) request. 
     
     
       5. The method of  claim 4 , further comprising repeating said steps of obtaining said relayed request, searching in said database, sending said query, obtaining said dynamic host control protocol relay device information, and storing said dynamic host control protocol relay device information, for an additional relayed request, said additional relayed request comprising an Internet Protocol Version 4 (IPv4) request. 
     
     
       6. The method of  claim 3 , further comprising:
 repeating said steps of obtaining said relayed request, and searching in said database, for a relayed request from another, known, dynamic host control protocol relay device relaying a request of another client; 
 responsive to at least one given internet protocol address of said known dynamic host control protocol relay device being found in said database in said repeated searching step, searching said database for a subnet containing an address of said another client. 
 
     
     
       7. The method of  claim 6 , further comprising, responsive to said subnet not being found in said database, rediscovering said known, dynamic host control protocol relay device. 
     
     
       8. The method of  claim 3 , wherein said sending of said query, from said topology map engine, back to said dynamic host control protocol relay device, for said dynamic host control protocol relay device information, comprises sending said query as a simple network management protocol message. 
     
     
       9. The method of  claim 3 , wherein, in said step of obtaining said relayed request, said relayed request comprises an Internet Protocol Version 4 (IPv4) request. 
     
     
       10. The method of  claim 3 , wherein, in said steps of sending said query and obtaining said dynamic host control protocol relay device information, said permanent identifier of said dynamic host control protocol relay device comprises a hostname. 
     
     
       11. The method of  claim 3 , wherein, in said steps of sending said query and obtaining said dynamic host control protocol relay device information, said permanent identifier of said dynamic host control protocol relay device comprises a serial number. 
     
     
       12. The method of  claim 3 , wherein, in said steps of sending said query and obtaining said dynamic host control protocol relay device information, said permanent identifier of said dynamic host control protocol relay device comprises a loopback internet protocol address. 
     
     
       13. The method of  claim 3 , wherein, in said steps of obtaining said relayed request, sending said query, and obtaining said dynamic host control protocol relay device information, said dynamic host control protocol relay device comprises a cable modem termination system. 
     
     
       14. The method of  claim 3 , wherein, in said steps of obtaining said relayed request, sending said query, and obtaining said dynamic host control protocol relay device information, said dynamic host control protocol relay device comprises a digital subscriber line access multiplexer. 
     
     
       15. The method of  claim 3 , further comprising:
 repeating said steps of obtaining said relayed request, searching in said database, sending said query, obtaining said dynamic host control protocol relay device information, and storing said dynamic host control protocol relay device information, for a plurality of additional relayed requests from a plurality of additional dynamic host control protocol relay devices; and 
 based on said repeated steps, maintaining a historical log. 
 
     
     
       16. The method of  claim 3 , wherein, in said steps of querying for and obtaining said dynamic host control protocol relay information, said internet protocol addresses assigned to said network interfaces of said dynamic host control protocol relay device comprise said at least one given internet protocol address, and at least one additional statically allocated internet protocol address. 
     
     
       17. The method of  claim 3 , wherein:
 said obtaining of said relayed request is carried out by a lease request receiver module, embodied on a non-transitory computer readable medium, executing on at least one hardware processor; 
 said searching in said database is carried out by said lease request receiver module executing on said at least one hardware processor; 
 said sending of said query is carried out by an interrogator module, embodied on said non-transitory computer readable medium, executing on said at least one hardware processor; 
 said obtaining of said dynamic host control protocol relay device information is carried out by said lease request receiver module executing on said at least one hardware processor; and 
 said storing of said dynamic host control protocol relay device information in said database is carried out by said lease request receiver module executing on said at least one hardware processor. 
 
     
     
       18. A method comprising the steps of:
 obtaining, at a topology map engine, from a dynamic host control protocol relay device, a relayed request, of a client, for a dynamic host control protocol lease, said relayed request having at least one given internet protocol address of said dynamic host control protocol relay device inserted therein; 
 searching, in a database, for said at least one given internet protocol address of said dynamic host control protocol relay device; 
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, obtaining, at said topology map engine, from said dynamic host control protocol relay device, dynamic host control protocol relay device information comprising at least:
 an identifier of said dynamic host control protocol relay device; and 
 at least one network interface of said dynamic host control protocol relay device and any internet protocol address assigned to said at least one network interface of said dynamic host control protocol relay device; 
 
 storing said dynamic host control protocol relay device information in said database; and 
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, sending a query, from said topology map engine, back to said dynamic host control protocol relay device, for said dynamic host control protocol relay device information; 
 wherein in said step of obtaining said dynamic host control protocol relay device information, said identifier comprises a permanent identifier; 
 wherein said dynamic host control protocol relay device information comprises:
 said permanent identifier of said dynamic host control protocol relay device; 
 all network interfaces of said dynamic host control protocol relay device; and 
 all internet protocol addresses, including said at least one given internet protocol address, assigned to said network interfaces of said dynamic host control protocol relay device; and 
 
 wherein, in said steps of sending said query and obtaining said dynamic host control protocol relay device information, said permanent identifier of said dynamic host control protocol relay device comprises a loopback internet protocol address. 
 
     
     
       19. The method of  claim 18 , wherein, in said obtaining and searching steps, said database and said topology map engine are collocated in a data center. 
     
     
       20. A method comprising the steps of:
 obtaining, at a topology map engine, from a dynamic host control protocol relay device, a relayed request, of a client, for a dynamic host control protocol lease, said relayed request having at least one given internet protocol address of said dynamic host control protocol relay device inserted therein; 
 searching, in a database, for said at least one given internet protocol address of said dynamic host control protocol relay device; 
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, obtaining, at said topology map engine, from said dynamic host control protocol relay device, dynamic host control protocol relay device information comprising at least:
 an identifier of said dynamic host control protocol relay device; and 
 at least one network interface of said dynamic host control protocol relay device and any internet protocol address assigned to said at least one network interface of said dynamic host control protocol relay device; 
 
 storing said dynamic host control protocol relay device information in said database; and 
 if said at least one given internet protocol address of said dynamic host control protocol relay device is not found in said database in said searching step, sending a query, from said topology map engine, back to said dynamic host control protocol relay device, for said dynamic host control protocol relay device information; 
 wherein in said step of obtaining said dynamic host control protocol relay device information, said identifier comprises a permanent identifier; 
 wherein said dynamic host control protocol relay device information comprises:
 said permanent identifier of said dynamic host control protocol relay device; 
 all network interfaces of said dynamic host control protocol relay device; and 
 all internet protocol addresses, including said at least one given internet protocol address, assigned to said network interfaces of said dynamic host control protocol relay device; and 
 
 wherein, in said steps of querying for and obtaining said dynamic host control protocol relay information, said internet protocol addresses assigned to said network interfaces of said dynamic host control protocol relay device comprise said at least one given internet protocol address, and at least one additional statically allocated internet protocol address. 
 
     
     
       21. The method of  claim 20 , wherein, in said obtaining and searching steps, said database and said topology map engine are collocated in a data center.